It was most odd. Four decades after I’d walked into The Sun to start my first shift as a news sub editor, I was sitting in a small theatre in the heart of La La Labour-land (the Almeida in Corbyn’s Islington) watching a play where I knew all the characters, as I both worked with them and worshipped them.

There was Rupert Murdoch. There was Sun editor Larry Lamb, his deputy Bernard Shrimsley, Page Three photographer Beverley Goodway, and even production supremo Ray Mills who, due to his northern background, was known as Biffo — Big Ignorant Fucker From Oldham. How much would that acronym be worth at an employment tribunal today?

The ensemble had been put together by James Graham (who wrote the political hit This House) for his new offering Ink, which details how a combo of Rupert’s restless energy and Lamb’s creative talent saw The Sun go from a failing 650,000 circulation to 4,000,000, passing its bitter rival the Daily Mirror and destroying its claim to be the legitimate voice of the working classes.

The play is set in the 1970s, as was This House, and was immaculately researched by Graham, so much so that it often had the feel of a documentary. Although I was too far down the ladder to be privy to the conversations between Rupert and Larry, their dialogue had the ring of truth about it.

I could actually hear Rupert (Bertie Carvel) saying this line when talking to Larry (Richard Coyle): ‘You’re still trying to beat them by fighting on their terms. Let it go. Do you know when I hear “codes” and “traditions”, I hear the rules as written by those who benefit from them to stop others treading on their turf.’

I’m sure he would have said that then and would say it again today. So might Corbyn. A worrying link.

I don’t think that Graham captured the chip-on-both-shoulders aspect of Larry, a miner’s son brought up in the Yorkshire pit village of Fitzwilliam (which also welcomed Geoffrey Boycott into the world). He was always resentful at not going to university.

Unbelievably, he was a trade union official before going into journalism but saw the light when falling under the gaze of Margaret Thatcher. He was knighted towards the end of his Sun tenure (always a mistake for a serving editor) and I suggested the headline: Sir Loin of Lamb. The gag fell flat.

One thing Graham did get right was Larry’s love of a whisky. There was hardly a scene where he wasn’t pouring himself a drink. I was told that Rupert was quite shocked at seeing Larry and his colleagues enjoying a sherbet in the office, exclaiming, ‘They’re drinking whisky out of plant pots.’

On another occasion, the two men were having dinner at the Savoy Grill, a regular hangout for the editor, when Rupert ordered a bottle of the house wine and the sommelier responded, ‘Mr Lamb wouldn’t wash his car in that, Mr Murdoch.’ Without looking up Rupert responded, ‘Well I would… we’ll stick to the house.’

For me the most dramatic moment in the play came with the true story of the kidnapping and murder — although the body has never been found — of Muriel McKay, the wife of Rupert’s trusted deputy chairman Sir Alick McKay.

The kidnappers mistook her for Rupert’s then wife Anna. They had followed the Murdochs Rolls-Royce to a house in Wimbledon but what they didn’t know was that the Murdochs were in Australia and Sir Alick had borrowed the car.

The scene where Sir Alick turns on Larry for publishing a note from Muriel telling her husband, ‘Please do something to get me home. What have I done to deserve this?’ is compelling, with him pushing over the editor’s desk, then being joined by Rupert and, strangely, in the end, by Larry.

I presume the suggestion is that the publication hastened Muriel’s murder. I have no idea if that has any basis in fact, but I do know that it was riveting and probably worth the ticket price on its own.

The oddest aspect of the play was the audience. It was pretty clear that none of them had ever bought The Sun nor would ever have a good word to say about it. I spotted one theatre goer wearing a T-shirt with the words: ‘I’m the man the Daily Mail warned you about’.

At three hours I found the play too long, and the play’s director, Rupert Goold, would do well to remember Fred Astaire’s line: get it perfect — and then cut two minutes. In Ink’s case that should be 30 minutes.